POS1409 ASSOCIATION BETWEEN SHORT-TERM EXPOSURE TO ENVIRONMENTAL AIR POLLUTION AND PSORIASIS FLARE
Authors: G. Adami, F. Bellinato, A. Fassio, C. Benini, G. Girolomoni, P. Gisondi, M. Rossini
Journal: Annals of the Rheumatic Diseases (2022)

Background Psoriasis is a chronic inflammatory disease with a relapsing-remitting course. Selected environmental factors such as infections, stressful life events or drugs may trigger disease flares. Whether the air pollution could trigger psoriasis flares is still unknown. Objectives To investigate whether the short-term exposure to environmental air pollution is associated to psoriasis flares. Methods Observational study with both case-crossover and cross-sectional design was conducted. We retrospectively analyzed longitudinal data from 2013 to 2020 of patients with psoriasis attending the outpatient dermatologic clinic of the University Hospital of Verona. For the case-cross over analysis patients with at least one disease flare, defined as PASI increase ≥5 between 2 consecutive assessments in a time frame of 3-4 months, were considered. In the case-crossover analysis each patient serves as its own control; the exposure of interest is compared in two different periods in the same group of patients followed longitudinally (Figure 1). For the cross-sectional analysis, patients receiving any systemic treatment for ≥6 months, with ≥2 consecutive PASI assessment were included. We compared the mean and cumulative (area under the curve) concentrations of several air pollutants (CO, NO2, NOx, C6H6, PM10 and PM2.5) in the 60 days preceding the psoriasis flare and the control visits. Results A total of 957 patients with plaque psoriasis with 4,398 follow-up visits were included in the study. More than 15,000 measurements of air pollutants concentration from the official, open-source, bulletin of the Italian Institute for Environmental Protection and Research (ISPRA) were retrieved. Among the overall cohort, 369 (38.6%) patients with psoriasis flare were included in the case-crossover study. We found that concentrations of all pollutants were significantly higher in the 60 days before psoriasis flare (median PASI at the flare 12, IQR 9-18), compared to the control visit (median PASI 1, IQR 1-3, p &lt;0.0001). In the cross-sectional analysis, exposure to mean PM10 over 20 μg/m3 and mean PM2.5 over 15 μg/m3 in the 60 days before assessment were associated with a higher risk of PASI ≥5 point worsening, aOR 1.55, 95% CI 1.21-1.99 and aOR 1.25, 95% CI 1.0-1.57, respectively (Figure 1). Sensitivity analyses that stratified for trimester of evaluation, with various lag of exposure and adjusting for type of treatment yielded similar results. Conclusion Air pollution may be a trigger factor for psoriasis flare. Disclosure of Interests Giovanni Adami Speakers bureau: Galapagos, Theramex, Francesco Bellinato: None declared, Angelo Fassio: None declared, Camilla Benini: None declared, Giampiero Girolomoni Shareholder of: AbbVie, Abiogen, Almirall, Amgen, Biogen, Bristol-Meyers Squibb, Eli-Lilly, Galderma, Genzyme, Leo Pharma, Pfizer, Regeneron, Samsung and Sanofi, Paolo Gisondi Shareholder of: Abbvie, Almirall, Amgen, Biogen, Eli Lilly, Jansenn, Novartis, Sanofi, UCB, Maurizio Rossini Shareholder of: Abbvie, Amgen, Bms, Eli Lilly, Galapagos, Novartis, Pfizer, Sandoz, Theramex, Ucb